Stix - yep. miraclebeam laser in the second pic. Both of my proper tanks have two laser modules and one blue LED module. Makes them look really good after lights out especially if the room lights are turned right down. It took me a while to get them in the right place and pointing in the right directions, but in my opinion, well worth it. See pic below for a long exposure pic of the tank with the lasers and LED showing up nicely.
Hi Nikki - the RTBS are about 2 1/2" to 3" in length now. When I got them they were a little over 1". Going to have to think about rehoming them soon as they are getting a bit too big for the tank now.
Cheers, Eddie